Let x = number of coach tickets
Then 92 - x = number of sleeper tickets
Our equation becomes $121x + $282(92 - x) = $19826
Expanding, we get $121x + $25944 - 282x = $19826
Combining, we get -161x = -6118; multiply both sides by -1
to get 161x = 6118; and x = 38, so 92 - x = 54
Proof: 38 x $121 + 54 x $282 = 19826